the EDITOR'S column L.T.Hallett,
Editor
iiTEAsuEEMENT OF physical quantities has been the driving force behind m a n y of the scientific advances m a n has made in his continuous quest for knowledge and domination of the physical universe. T h e present-day need to improve the range and accuracy of measurements is stressed in the "1961 Research Highlights of the National B u r e a u of S t a n d a r d s . " This government agency, set up 60 years ago by Congress to establish and maintain national standards of measurements, reports impressive progress in measurement s t a n d a r d s in electricity, metrology, heat, radiation physics, mechanics, radio standards, and building research. T h e unit of electrical resistance was redetermined by comparison with a capacitor whose resistance was calculated very accurately from its dimensions. The previous N B S value for the ohm agreed with the new value to within ca. 2 parts in 10 e and the new value was selfconsistent to 1 p a r t in 10 6 . T h e Bureau has developed also a differential thermocouple voltmeter to convert d.c. measurements derived from fundamental standards into a.c. measurements used in electric generators, radio, and electronics. T h e n a t u r a l frequency of the cesium atom, the N B S atomic s t a n d a r d of frequency, agreed to 1 or 2 parts in 10 10 with its Swiss and British counterparts and NBS standard frequency broadcasts were monitored with it. T h e use of this atomic frequency s t a n d a r d might be responsible, at some future date, for the redefinition of the second. As modern technology develops, very high temperatures and pressures are used; hence, standards and measurement techniques are
tyJeJxUt
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TECHNICON CONTROLS, INC. R E S E A R C H PARK · CHAUNCEY, Circle No. 149 on Readers' Service Card
N.Y.
VOL. 34, NO. 8, JULY 1962
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